In this double-blinded, placebo-controlled, fixed-dose, study patients will be randomly assigned to take placebo or 20 mg tadalafil thrice weekly for 6 weeks. After 6 weeks a wash out period of 2 week will be observed and then the two groups will be switched over to receive the other drug. We planned a priori to include 20 patients. The concomitant medication for treatment of rheumatic disease remained unchanged during the whole study. Patient will undergo clinical and lab evaluation for organ damage for kidney and lungs. ECHO heart will be done at base line to assess the PAH and LV function and repeated at the end of the study. Blood pressure will be recorded at each visit. A physician unaware of the treatment group will record skin score and appearance of new cutaneous ulcers. The primary outcome variables will be frequency and duration of Raynauds attacks, evolution of trophic digital lesions and change in flow mediated dilatation of the brachial artery. Flow mediated dilatation of the brachial artery will be done at baseline 6 and 12 weeks.

Male or female subjects between the ages of 18 years and 60 years will be selected for the study if they have a clinical diagnosis of Raynaud's phenomenon secondary to systemic sclerosis (scleroderma). Raynaud's phenomenon is defined as a history of cold sensitivity associated with colour changes of cyanosis or pallor, as well as a history of at least 4 attacks per week during two pre-trial period even with treatment with other vasodilators. The diagnosis of scleroderma is defined by the American College of Rheumatology (ACR) criteria or by the presence of at least 3 of the 5 features of the CREST syndrome (calcinosis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, telangiectasias).

Exclusion Criteria:

Patients will be excluded if they have:

Symptomatic orthostatic hypotension

Evidence of current malignancy

History of sympathectomy

Upper extremity deep vein thrombosis or lymphedema within 3 months

Recent surgical procedure requiring general anesthesia

AMI, unstable angina, strokes and TIA within the past three months

Smoking

Use of any investigational drug within 30 days of the study sessions

Use of medications that might interfere with tadalafil like nitrates and alpha adrenergic blockers that have vasoactive effects, and patients taking potent inhibitors of CYP3A4 such as ritonavir, ketoconazole, and itraconazole, erythromycin, itraconazole, and grapefruit juice

Patients taking alcohol

Patients with bleeding disorders

Significant active peptic ulceration

Current pregnancy

Current breast-feeding

Contacts and Locations

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study.
To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below.
For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00626665